Inside your autoresponder you should have the option to email your UNOPENs and NON Clickers.
So basically you can email people who haven't opened your email OR haven't clicked the link your email..
This is a quick and easy way to squeeze more clicks from you list and make more money.
Obviously only do this if the offer you're promoting is converting really well and you don't want to burn your list on the same offer.
This way you don't have to blast your entire list and get a ton of complaints and unsubscribes.
BTW - I do this multiple times until I squeeze crazy clicks from tiny lists!